In a vulcanization system for vulcanizing a plurality of tire sizes, in order to achieve a high productivity, there has hitherto been conducted a method wherein tires are vulcanized in a plurality of vulcanization machines for a shortest vulcanizing time for each tire size. According to this method, however, if the size of the tire to be vulcanized in the vulcanization machine differs, the vulcanizing time differs, so that a tact time differs for each vulcanization machine. This is problematic because even if green tires are shaped at a constant tact time, a vast middle storage space for the green tires is necessary between the tire shaping system and the tire vulcanizing system to prevent the lack of stock of the green tires.
The invention has been made considering the above problem and provides a size allocating method for tire vulcanization capable of efficiently vulcanizing at a constant tact time without requiring the middle storage for the green tires even if tires of a plurality of sizes are mixed, and a method of producing tires as well as a setting method of a vulcanization process.